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[Music]

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so isat2 provides bathymetric

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measurements and what that means is

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measurements beneath the surface of the

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water so we can map the topography

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underwater this is interesting because

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you might notice the really strong

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returns from beneath the surface of the

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water although this is a pretty shallow

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area about 10 meters or 30 feet deep the

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signal is quite strong just as strong as

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from the surface of the water the reason

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that is is there's a lot of limestone in

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the deposits there and it's highly

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reflective so isat2 gets a lot of

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reflected photons back from those laser

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shots

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[Music]

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in this profile the vegetation is

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dominated by shrub mapani which is

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typically in a two to three meter range

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and there's also some mapani and acacia

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trees that typically aren't the four to

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six meter height range

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something that scientists need to

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understand to quantify is where carbon

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is being taken up and where it is

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already being stored

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because much of the effort related to

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mapping global biomass has been really

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focused in the tropics where the trees

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are large and the biomass is high many

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of these savannah and woodland

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ecosystems tend to get neglected or are

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poorly characterized in global carbon

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now one of the unique things about

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icesat too is it's actually able to see

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down into the valleys of these very

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steep topography areas where the

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glaciers are and so there's other

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instruments like radar that aren't able

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to see the glaciers all the way down in

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the valleys and so icesat-2 is going to

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let us measure the changes in mountain

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glaciers so we can assess how they're

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responding to changes in climate and

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what potential they have to contribute

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to both sea level rise in the future but

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also changes in water resources

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glaciers in this region have been

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experiencing rapid rates of thinning and

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that thinning is in response to changes

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in climate and not only are these

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glaciers thinning but as they thin

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there's less force pulling them downward

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and that less force pulling them

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downward is causing them to actually

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slow down so in high mountain asia we

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actually have glaciers that are thinning

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and slowing down as they respond to